1. RAS National Astronomy Meeting 2006 3-7 April 2006, University of Leicester, UK The XMM-Newton Slew Survey The excellent sensitivity of the XMM-Newton satellite is strikingly apparent while manoeuvering between observation targets. These slew observations, yielding only at most 12 seconds of on-source time, constitute a hard-band 2-12 keV survey ten times deeper than all others all-sky surveys and a soft-band 0.2-2 keV survey comparable with the ROSAT all-sky survey. Here processing challenges in the production of the First XMM-Newton Slew catalogue (XMMSL1) and highlights are outlined. Within the ~6300 square degrees uniformly covered and processed (~15% of the sky), of order of 4000 sources have been detected. Their correlation with other catalogues reveal ~50% of identifications, including a great variety of source types. Observations and data analysis Observations: EPIC-pn slew observations in FF, eFF and LW with Medium filter. Data processing: Three different energy bands are processed independently: Three different energy bands are processed independently: total band (0.2–12 keV) soft band (0.2–2 keV) hard band (2–12 keV) Slew observations are subdivided into 1 square degree images to maintain astrometry (Fig. 2). Slew observations are subdivided into 1 square degree images to maintain astrometry (Fig. 2). Sky positions are recalculated using a special Attitude file: Raw Attitude File (RAF) subtracted by 0.75 seconds from every entry, timing error that is due to a delay of the star tracker CCDs (Fig. 3). Sky positions are recalculated using a special Attitude file: Raw Attitude File (RAF) subtracted by 0.75 seconds from every entry, timing error that is due to a delay of the star tracker CCDs (Fig. 3). Images and exposure maps are created. They are produced containing only single pixel events in the 0.2-0.5 keV band, plus single and double events in the band 0.5-12 keV. Images and exposure maps are created. They are produced containing only single pixel events in the 0.2-0.5 keV band, plus single and double events in the band 0.5-12 keV. Source searching is performed using a near standard pipeline eboxdetect/emldetect tuned for ~zero background. The low background of the observations and the tight PSF give good sensitivity to detect extended sources (Fig. 4). Source searching is performed using a near standard pipeline eboxdetect/emldetect tuned for ~zero background. The low background of the observations and the tight PSF give good sensitivity to detect extended sources (Fig. 4). Detections in different bands are merged to produce unique source entries. Detections in different bands are merged to produce unique source entries. Flagging spurious sources produced by systematic effects in the instruments and detection software. Several cases: false detection, within extended source, within halo of bright source (Fig. 5), position suspect, source near edge, high background. Flagging spurious sources produced by systematic effects in the instruments and detection software. Several cases: false detection, within extended source, within halo of bright source (Fig. 5), position suspect, source near edge, high background. Source identification and sanity checks Source identification and sanity checks ESAC The XMM-Newton Slew Survey and The First Catalogue (XMMSL1) Fig 4. Upper panel: X-ray contours of the slew source plotted over the optical image of the Abell 2029 cluster. Bottom panel: The radial profile of the source (solid line) shows that the source is extended with respect to the PSF (dashed line). M.P. Esquej a, R.D. Saxton b, A.M. Read c, M. J. Freyberg a, B. Altieri b a Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85784 Garching, Germany b European Space Agency (ESA), European Space Astronomy Centre (ESAC), Villafranca, Apartado 50727, 28080 Madrid, Spain c Dept. of Physics and Astronomy, Leicester University, Leicester LE1 7RH, U.K. Current status 219 slews processed Source detections (det_ml>8): 4179 in total band, 2752 in soft band, 845 in hard band. Number of sources (merging detections in different energy bands): 5200 sources Spurious sources: 532 Some overlap: 105 sources seen in more than one slew Average slew length: ~70 degrees Average on-source time: ~7 seconds Positional accuracy: 8 arcsec Source density: ~0.65 sources per square degree Sky coverage: ~6300 square degrees (~15% of the sky) Fig 3. Comparison of data processing with different attitude files used for the astrometry reconstruction. Right images: detected slew source in the total band. Left images: position of the slew source overplotted on a DSS image. Top panel: source detected with the AHF as attitude file, the shift between the optical and the slew position is obvious. Bottom panel: corrected slew source position using the modified RAF for the attitude reconstruction. We can clearly see the difference between both processings and the improvement with the new attitude reconstruction. Fig 2. Slew observation performed with the EPIC- pn camera. Red boxes show subimages for processing. Fig 5. Extended source detected in revolution 0880. The real slew source is red circled. Spurious detections within the halo of this bright source are shown in light blue. The catalogue Two catalogues have been produced: Total catalogue: all detected sources (det_ml>8). Total catalogue: all detected sources (det_ml>8). Clean catalogue: including det_ml>14 sources and det_ml>10 & (high energy) bg_rate 14 sources and det_ml>10 & (high energy) bg_rate<3 sources. Each one of the catalogue entries has columns related to: Details of the observations. Details of the observations. Source parameters in the different detection bands from the source detection: counts, flux, extension, etc. Source parameters in the different detection bands from the source detection: counts, flux, extension, etc. Flags to qualify the sources. Flags to qualify the sources. Identifications: one derived from cross-correlations with different astronomical databases and catalogues and a RASS counterpart. Identifications: one derived from cross-correlations with different astronomical databases and catalogues and a RASS counterpart. Publication: April 2006 Available via the XMM-Newton Science Archive (XSA) Fig 6. 3D distribution of the XMMSL1 sources in galactic coordinates Flux limits of X-ray surveys in the soft band (left panel) and the hard band (right panel). Fluxes for the XMM-slew survey have been calculated for a source with DET_ML=10 and passing through the centre of the field of view. These fluxes were derived from count rates based on energy conversion factors assuming an absorbed power-law model with NH=3.0·10 20 cm 2 and slope 1.7 Fig 1. Flux limits of X-ray surveys in the soft band (left panel) and the hard band (right panel). Fluxes for the XMM-slew survey have been calculated for a source with DET_ML=10 and passing through the centre of the field of view. These fluxes were derived from count rates based on energy conversion factors assuming an absorbed power-law model with NH=3.0·10 20 cm 2 and slope 1.7